Aeroplane element and process of making same and product of said process



G. BLENIO AEROP'LANE ELEMENT AND PROCESS 0F MAKlNG SAME AND PRODUCT OF SALD PROCESS.

' APPLlcATloN man JAN. 11. |918.

1 $27,941, PatentedSept. 5, 1'922.

lik/52.2. [Q

Varnish Pyrxyll atente Sept `5, 19220 GUIDO BLENIO, OF NEW YORK, N.

PAINT & PRODUCTS CORPORATION, O

DELAWARE. v

AEROPL'ANR lminimaux: AND PROCESS or MAKING SAME AND PRODUCT OF SAID PROCESS.

Application filed January 11, 1913. Serial No. 2115419.

To all 'whom t may concern Be it known that I, GUIDO BLENIO, a subject of the King of Ital residing at New York, in the county of Niiw York and State of New York, have invented certain new and useful Improvementsl in Aeroplane Elements and Processes of Making Same and Products of said Processes, of which the following is a specification. I

This invention relates to aeroplane elements and processes of making same and products of said processes; and it comprises as a new article an airship plane of trussed cellular wooden construction enclosed in fabric under tension, said fabric being impregnated with fireproofing 'salts and carrying a facing layer of relatively damp orZ hygroscopic flame-proof material shielded and sealed in against access of air'by one Or more thin impermeable films of waterproofing material, said films being further protected by a varnish or paint coating; said cellular wooden construction being also advantageously protected insimilar manner; and it also comprises a method of making a protected fabrlc foraeroplanes and other purposes wherein a fabric islfirst impregnated with fireproofing salts somewhat dried, coated with a colloid hygroscopic` material, such as glue, sharply dried andcoated with a thin waterproofing film, 'such as pyroxylin, whole finally being painted Or varnished; and it further comprises as a new\article a layer of textile fabric impregnated with fireproofing salts and having One/or both sides carrying a flame-proof colloid layer of more or less/damp nature, such as glue ycontaining hygroscopic materials, and faced with a thin\layer of waterproofing material, such as pyroxylin, this layer being in turn, if -V desired, mechanically protected 'by a coat-v ingv of paint -or varnish; all as more fully hereinafter set forth and as claimed.

Planes for .aerial work are built of a .trussed cellular wooden framework with a .sheet of fabric stretched over and covering yboth sides.. Much is required, and more is desired, Ofthis fabric. It must be strong, light and taut; andthe tautness must not vary according to thehumidity. It should be impermeable to air and water. And it is highly desirable that it be fireproof as well.' Canvas (either linen or cotton) is the textile fabric ordinarily employed and to impart it the other variety of dopes have been proposed. For the most part, these are ordinarily waterproofing compositions and materials, rubber, pyroxylin, varnishes, etc. Unfortunatel most of the materials used for waterprOo 'ng are quite as combustible as the canvas itself, andoften more so. Pyroxylin, in its various commerical forms of celluloid, colloolion cotton, gun cotton etc., is one of the best of these Waterproo ng materials for aeroplane work, and is largely used, but of course it is highly combustible. In the e'ort to Obviate its inflammability 'it is Often used admixed with vvarious hygroscopic salts (calcium chlorid, etc.) or mineral matters; but in these admixtures the good qualities of the `pyroXylin for the present purposes are largely forfeited. The same applies to most of the ordinary varnishesthe less inflammable they are, as a rule', the less' efficient they are for waterproofing.

One of the best materials, probably, is cellulose acetate which isvnot readily infiammable-nb more so than canvas itself.

in any event, and which when used on the canvas fills up the pores, and by reducing the air content of the ,mability Any really efficient fireproofing composition must contain either moisture or ammonia salts; water vapors and' ammonia gas being the only really efficient, protectively acting fire extinguishing means. Any insoluble solid mineral material, as such, does not detract from inflammability.' ery many propositions have been made for using moist materials in connection" with waterproofing substances to produce compound dopes which were both waterproof and fireproof. For obvious reasons, however, these have not beensatisfactory.

yFor fireproofing purposes, as stated, the material should contain either water or ammonia or both. There are very many salts which contain water -Of crystallization. Ordinary crystallized sodium sulfate or qualities desired a wide- Y., AssIGNOR, BY MEsNE AssIGNMENTs,-TO RLENIO F NEW YORK, N. Y., A CORPORATION or fabric reduces its infiam- Glaubers salt, for instance, contains more than half its weight of: water of crystallization. Borax, alum, sulfate of alumina, sodium phosphate, etc., also contain much water of crystallization. Calcium chlorid, magnesium chlorid and many other salts are what are known asdeliquescent. Theytend to take up water from the air with formation of moist or liquid material. Many other salts contain ammonia in large amounts, as for instance ammonium sulfate, ammonium phosphate, etc., and some contain both water and ammonia, as for instance microcosmic salt (sodium ammonium phosphate), ammonia magnesium phosphate,'etc. Any of these salts is an efficient fireproofing material when used to impregnate vegetable fabrics for the reason thatwhen heat is a plied flame stiing vapors are evolved. llut they all have the objection that theirrelation to the humidity of the atmosphere is constantly varying; in dry weather they tend to lose moisture and in damp weather they tend to take it up. There are very many other materials of organic origin which are more or less fire roof in the sense that they are damp. (grdinary glueA does not burn readily and when it is moist resists flame very well.l

In the present invention I utilize the statedprinciples and materials to produce airship planes which have the desired combination of properties; being both weather or waterproof and flame-proof in the sense that they will not take re from burning gasoline or incendiary projectiles, etc. To do this, dope which can be applied to the aeroplane surface and will at once produce all the desired results, I use the various materials in a methodical way so as to produce what may be termed a laminated or built up product in'which the textile fabric itself is merely one layer or element. In so doing, I ordinarily apply the layer of textile fabric to the trussed wooden structure and make it as taut as may be. I then impregnate the fabric-'with a solution of fireproofing salts. While almost any hygroscopic salt, salt containilg water of crystallization or ammoni 1n salt may be used, in practice I find ammonium phosphate advantageous. In order to producej a more or less gelatinous character of the impregnant in the fabric and prevent any possible segregation in crystalline form I usually employ with the ammonium phosphate more or less aluminum sulfate. This gives me a mixture containing some sulfate of ammonia and some phosphate of alumina. This mixture Iapply to the fabric with the aid of a brush or a spray, taking care that the fabric is wet completely through. The fabric is next dried Ybut not absolutely so; I do not wish to produce a crystallization of dry material in the fabric in lieu of trying to make one single or to drive off Water of crystallization and ammonia. I merely wish it dry enough for the next coating. On the dried lsurface I next yapply a layer of thick glue solution containing fireproong salts, such as ammonium phosphate, in solution. It should,

also contain something hygroscopic, such as calcium chlorid, glycerin, sugar, etc. This layer I now dry in place, drying rather sharply so as to produce a dry surface while not expelling all the moisture from the interior. To this dried surface I next apply a thinor film `coating of a good weatherproof material. A pyroxylin solution is advantageous for this purpose. The pyroxylin may be dissolved in amyl acetate, acetone or anynother suitable quick drying solvent. On

evaporation of the solvent the fabric and the glue layer, both of which are somewhat moist, though not very much so, are effectually sealed in by the pyroxylin while the pyroxylin layer itself is so ythin as to be not readily inflammable. -Inforder to avoid possibility of any bare spaces it is in general advisable to apply the desired amount of pyroxylin as a number of successive very thin films rather thanas one coat, the coating being dried before each new application.

As so far stated, it will be observed that the cellular frame is completely enclosed in a layer of fabric which is somewhat moist and has been fireproofed by various salts. This fabric in turn is enclosed by a layer of an uninflammable glue also containing some moisture; and in turn this glue layer is enclosed by a continuous very of waterproofing composition. This film seals in everything; there is no possibility of evaporation from the glue layer, the fabric or the enclosed space within the cellular framework; In order to perfect still further this sealingin effect I find it better to apply the successive coats of pyroxylin thin film' varnish with a thin spacing layer of glue v between them. This obviates in large measure osmotic transference of moisture.

v; The application of moist materials to the canvas tautens it and since theamount of moisture must remain const-ant because of the sealing in, the tightness will not vary with weather or other` conditions. y I have therefore produced an article which is fireyproof, since no application of flame will 25 With this diluted No. l may impregnate the y ordinarily *finally apply a thin coating of a good paint or varnish, such as a spar varnish. An ordinary limit for the weight of aeroplane facingsvis about 7 ounces per yard, and T can produce all the required strength, with the other desirable results stated, within this limit by the use of a aounce fabric carrying not to exceed 3 ounces of my various other materials.

Tn a speciic embodiment if the present invent-ion in freproong and protecting an aeroplane element, such as the wing surface, T may proceedas follows: Presuming the trussed wooden framework to be assembled and ready for treatment T first brush it over thoroughly with a solution which T mayfhere call No. l. This solution T make by taking an ammonium phosphate solution neutral to litmus and of 15 Be. and adding to it suflicient aluminum sulfateto bring the density to about 17 Be. By reason of the interaction of the phosphate with the alumina there is produced a composition of a more or less thick character. Thisv composition T dilute with water to a densit of around -70 B.

woodwork. Thefabric is iixed to the woodwork-in the usual way, being stretched as taut as possible. T next brush it thoroughly with the diluted No. l composition, seeking to wet the fabric thoroughly therewith. This produces additional tensioning of the fabric and enhances the tautness. The plane is next dried to some extent. Since T desire to retain moisture, T do not dry thoroughly. The next treatment is with a ireprooing mechanically strong gelatin or glue. This composition, which T may call No. 2, T usually make b-y taking good strong glue or gelatin and swelling it in water for several hours, say over night. This swelled glue is next melted an a hygroscopic, softening material incoporated. Glycerin does -very well. F or each pound of swelled glue T may use, say, two ounces of glycerin. Tt

. is desirable also to add an antiseptic since of swelled in use this composition will of course remain more or less damp. A good antiseptic for this purpose is salicylic acid. T may use about one-fourth of an ounce for each pound lue.

`have a density of about 60 Be. With this No. 2 composition `T next coat all the exposed surfaces, using one or more coats applied with a brush or spray as "may be most convenient. The coated -plane is next dried somewhat. Tt is advantageous now to apply one or more thin coats4 of the glue solution Tn swelling the amountl of water# which the glue will take up varies with the addition of the No. l composition. The coated pla-ne is now sharply dried; that is T dry at a rather high temperature but not for a long time, the effort being to make the outer surface absolutely dry in order to receive the next coating, but not to drive out the moisture from the interior of the coating or from the fabric. The sharp dried surface now receives a thin coating of any convenientwaterprooling composition. Pyroxylin, or collodion cotton dissolved in amyl acetate and thinned do-wn with acetone is convenient. Tt is best to apply several ve thin b-rush coats, drying between each .coating in order to be able to attain an absolutely impervious sealing film without using too much material. lTn the case of pyroxylin it is highly undersirable that the total thickness of this sealing film shall be very great. After this pyroxylin film is applied it is advantageous to apply a thin coat of the glue solutio-n, using for this purpose solution with the addition of the fireprooling salts or No. l composition. This layer of glue should be very thin. JTfter its applicatlon it is dried sharply and another layer of pyroxylin applied; and so on, giving as manyalternate thin coats of pyroxylin and glue asmay be desired. Finally the whole assemblageis best painted or varnished to give mechanical protection. A good spar varnish is suitable for this purpose. Tt will be observed that in the article producedy as jfust described fireprooiing is attained by the use offireprooing salts and moisture in the glue. The glue has enough hygroscopic agent (glycerin in the example given) to keep it soft and pliable without forfeiting mechanical strength. The layer of glue really forms a mechanical element in the assemblage. This glue is preserved from mildewing, molding, fermenting, etc. by the antiseptic, the salicylic acid. And the whole assemblage is shielded from the action of air by the waterproofing composition. The principal element in the ireproofing of the assemblage is really the glue layer; the fireprooing of the fabric while useful not being so important. protects the fabric against access of flame. Tn one embodiment of my invention T may omit fireproofing the fabric altogether. As however the fabric in this situation would become moist and would be exposed to decay T advantageously impregnato it thoroughly with beeswax, paraffin, pitch, asphalt, etc. 0r it may be impregnated with rubber and cured. Tfind it best in this modification of my invention to use a good grade of beeswax or ceresin. This adds considerably to the mechanical strength of the cloth treated and permits the use of a lighter fabric for the same strength. Of course the fabric may be impregnated with ireproofing For the glue layer ceresin; but it is more convenient ordinarily to omit this fireproofing. Presuming the fabric has been impregnated with beeswax', either in a molten state or dissolved in a solvent, the No. 2 composition is applied as before' and the various other coatings applied in the order stated.

In the accompanying drawings I have shown, more or less diagrammatically, an airship pla-ne and a section of the covering illustrating my invention. It this showing Figure 1 is a longitudinal section through an aeroplane wing; and

Figure 2 is a vertical section through one sheat of fabric etc.' on a greatly enlarged sca e.

In Figure 1, element l is the usual trussed wooden framework carrying a canvas, linen, etc. textile fabric 2 which has been treated in accordance with the described invention. It is stretched tautly over the frame in the usual waywith its ends abutting as at 3, and is provided with'the overlapplng section of fabric 4 which is also treated in accordance with the present invention. The fabric is stitched at several points adjacent the` struts 5 as isindcated at 6.

Inl Figure 2 the warp and weft of the fabric are indicated by reference numeral 7. When the fireproofing solution is used it impregnates the fabric as is indicated in dotted 'lines throughout the warp and the weft threads. The fireproof glue layers which .are next applied are indicated by the referencel letters A and B. C indicates the sealing-in film, layer of pyroxylin, or whatever other waterproofing material may be employed.- As many layersof A, B and C as desired may be used as has been described. The uppermost layer D in Figure 2 indicates the final coatin of varnish. Either one or both sides of t e fabric may be thus treated.

The same methods of treatment may be usefully applied for the production of other materials intended to resist water or weather and flame, as for instance underwriters cloth,

- tents, balloons, etc.

In produclng the compound fabric for aeroplane wings it is of course not necessary to seal in the base of the assemblage since the two layers of protected cloth at the top and bottom of the wing protect each other. Where a cloth is lto be waterproofed and flame-proofed onvboth sides it is merely necessary to duplicate the treatment above described with regard to one side. In many articles however, as an underwriters cloth, it is not desired to waterproof the under side and such materials may be made exactly as above described. for an aeroplane wing. Of course. thread or yarn may be treated in the manner above described and then formed into a fabric. In this clase every thread of the fabric will contain fireproofing salts,

mamar carry a layer of glue or the like and be sealed in by a tenuous layer of waterproofing material. But it is ordinarily easier to treat the fabric itself.

In lieu of the glue more specifically mentioned ante, any other colloid material capable of giving moist strong films may be used in lieu thereof, such as algin, Irish moss, Iceland moss, concentrated waste sulfite liquid, viscose, etc. A good starch size, such as apparatin, is applicable. Such a mixture as is produced by dissolving borax in starch paste is applicable. A mixture of borax, sulfate of alumina and starch gives a good, strong coating material. In using glue or gelatin, I may employ the dry commercial articles; or Il may use the liquid materials which are ,variously known as size, glue size, etc. Low grade glues such as those made from stick may be used. As the waterproofing and film forming layer I regard pyroxylin in the form of celluloid or collodion cotton as best adapted, but a wide variety of other materials may be used, such as cellulose acetate, bakelite (a phenol formaldehyde condensation product) etc..k dinary varnishes are not well adapted since they require too thick a layer to produce impermeability. When Vpyroxylin is used" it may be softened or made flexible by camphor or castor oil in the usual manner; but it should not be loaded with hygroscopic salts as is sometimes done for producing a.

porating permanently moist material (with or without ammonia yielding materials, but

usually with) in the fabric, part of the water being present as moisture and partas what may be called latent moisture, that 1s, water of crystallization or constitution, and then sealing in the water and the ammonia with the aid of thin films'of something that is not dissolved or be affected by water and is impervious enough toinsulate the fireproofing materials against access of air.

In lieu of using glycerin asthe hygroscopic agent in the glue etc. layer I may of course use any other hygroscopic agent, as for instance, sugar, molasses, lucose, confectioners glucose, honey, glyco etc.

What I claim is l. The process of@ treating textile ima" teria-ls which comprises impregnating such material with a fireproofing chemical` and. applying a glue solution containingV hygroscopic materials, sealing in the treating materials so employed with a thin film of pyroxylin, applying a film of a glue solution,

' drying and again applying-a film of waterproofing material..

2. The process of treating textile materials -which comprises impregnating fabric with a solution of a fireproofing salt, drying somewhat, coating with a lue solution containing hygroscopic mater1als, sharply drying, treating with a waterproofing solution and once more drying.

3. The process of treating textile materials which comprises impregnating fabric with a solution of a fireproofing salt, drying somewhat, impregnating with a glue solution containing hygroscopic materials, sharply drying, treating with a waterproofing solution, drying, treating with a glue solution, once more drying and applying another waterproofing film.

4. The process of treating textile materials which comprises impregnatin such a material with fireproofing chemica s and anuninflammable size, sealing the impregnating materials in position by thiny films of a waterproofing material and finally coating the material with a' mechanically resistant coating. f

5. In the manufacture of aeroplane wings the process which comprises treating the frames thereof with a fireproofing material, stretching and fastening the fabric covering on the frames, treating the fabric with a moist fireproofing material while on the frames and sealing the same in place by a p As a new article of manufacture, a textile fabric having the threads or fibers impregnated with ,fireproofing chemicals and coated with moist uninflammable waterproofing material, and thin films of other lwaterproofing material sealing such chemicalsv and first mentioned waterproofing material in place.

.8. As a new article'of manufacture, a textile fabric having the threads or bers impregnated with fireproofingv chemicals and coated with a composition containing hy groscopic materials, and a film of Waterproofing material sealing such chemicals and y,

such compositions in place.

9. As a new article o'f manufacture, a textile fabric having `the threads or fibers impregnated with fireproofing chemicals and coated with a composition containing hygroscopic materials, and a plurality of waterproof films spaced and united by intervening films of a dried colloid composition sealing such chemicals and such hygroscopic materials in' place.

In testimony whereof, I affix my signature.

GUIDO BLENIO. 

